Perforated closed cell foam insulation, apparatus and method for perforating closed cell foam insulation, and insulated article

ABSTRACT

The present invention is directed to perforated closed cell foam insulation. A sheet of closed cell foam insulation has opposing first and second major surfaces, and a plurality of spaced openings extending from the first major surface to the second major surface. Apparatus and methods for perforating a sheet of closed cell foam insulation are also disclosed. The present invention also relates to an insulated metal panel including the disclosed perforated closed cell foam insulation.

FIELD OF THE INVENTION

The present invention is directed to perforated closed cell foam insulation. A sheet of closed cell foam insulation has opposing first and second major surfaces, and a plurality of spaced openings extending from the first major surface to the second major surface. Apparatus and methods for perforating a sheet of closed cell foam insulation are also disclosed. The present invention also relates to an insulated metal panel including the disclosed perforated closed cell foam insulation.

BACKGROUND OF THE INVENTION

Closed cell foam insulation (CCF) is used in various applications as a thermal and acoustic insulator, such as in HVAC appliances. CCF is a generic term used interchangeably for either elastomeric or polyethylene based insulation having a closed cell structure. It is typically produced using polymeric materials and blowing agents. When the blowing agent is introduced into the polymer, closed cell air pockets are formed. It is commonly available in sheets, rolls, and tubing. CCF has a smooth, durable external surface that resists dirt and moisture accumulation. The closed cell structure does not absorb any significant amounts of moisture. Rather, conventional CCF provides a barrier to vapor exchange, and therefore does not “breath” as does open cell insulation.

CCF is a preferred insulation for many applications. However, it may be difficult to install relatively large sheets of CCF without creating air pockets between the surface being insulated and the sheet of insulation, particularly when it is applied using an adhesive. Any air pockets that are created from improper installation may compromise the insulating properties of the insulation. In addition, the insulation tends to delaminate from the substrate in areas having air pockets. Any trapped air will not permeate out through the CCF due to its “non-breathable” and impermeable characteristics. In addition, any condensation and/or other moisture that develops on portions of the substrate in areas where air pockets were created will not permeate out through the CCF.

SUMMARY OF THE INVENTION

The present invention is directed to perforated closed cell foam insulation. A sheet of closed cell foam insulation has opposing first and second major surfaces, and a plurality of spaced openings extending from the first major surface to the second major surface.

An apparatus for perforating a sheet of closed cell foam insulation is also disclosed. The apparatus includes a supply section for holding sheet insulation, a nip roller spaced from the supply section, and an aerator roller. The nip roller has a cylindrical configuration and a motor operably associated therewith for causing axial rotation of the nip roller. The aerator roller has a plurality of spaced projections. The aerator roller is parallel to the nip roller and spaced from the nip roller a sufficient distance so that the sheet insulation is perforated by the spaced projections when passing therebetween.

An apparatus for perforating a sheet of closed cell foam insulation according to another embodiment is provided. The apparatus includes a supply section for holding sheet insulation, and a press spaced from the supply section. The press has a major surface including a plurality of spaced projections. An actuator is operably associated with the press, and causes the major surface to contact the sheet insulation when passing under the press so that the sheet insulation is perforated by the spaced projections.

A method of perforating closed cell foam insulation is provided. A supply of closed cell foam sheet insulation and a pair of rollers parallel and adjacent to each other are provided. One of the rollers has a plurality of spaced projections. The sheet insulation is passed between the rollers so that the spaced projections perforate the sheet insulation.

Another method of perforating closed cell foam insulation is disclosed. A supply of closed cell foam sheet insulation is provided. A press having a major surface including a plurality of spaced projections is provided. The sheet insulation is disposed under the press. The sheet insulation is pressed against the major surface so that the sheet insulation is perforated by the spaced projections.

The present invention also relates to an insulated metal panel, such as a panel of a HVAC cabinet. The panel includes a metal planar portion and a sheet of closed cell foam insulation. The insulation has a first major surface, which is adhered to the metal planar portion, and an opposing second major surface. A plurality of spaced openings extend from the first major surface to the second major surface.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of a perforated sheet of CCF according to the present invention;

FIG. 2 is a sectional view of a perforated sheet of CCF having an adhesive layer covering a major surface of the sheet, and a releasable liner material covering the adhesive layer;

FIG. 3 is a sectional view of an apparatus for perforating a sheet of CCF according to a first embodiment;

FIG. 4 is an elevational view of an aerator roller;

FIG. 5 is a sectional view of an apparatus for perforating a sheet of CCF according to another embodiment;

FIG. 6 is a fragmentary sectional view of a portion of the apparatus shown in FIG. 5;

FIG. 7 is a perspective view of an insulated metal panel according to the present invention;

FIG. 8 is a sectional view of an apparatus for perforating a sheet of CCF according to another embodiment; and

FIG. 9 is a perspective view of a press for perforating a sheet of CCF according to another embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS(S)

As best shown in FIG. 1, the present invention is directed to perforated closed cell foam insulation (CCF) comprising a sheet of CCF 10 having opposing first and second major surfaces 12, 14. A plurality of spaced openings 16 extend through sheet 10 from first major surface 12 to second major surface 14. Sheet 10 preferably has a thickness of at least about 0.030 inches, more preferably a thickness of between about 0.0625 inch and up to about 2.0 inch. Preferably, sheet 10 is formed from a polyethylene material.

I prefer that the openings 16 be uniformly distributed over sheet 10. The ultimate use of sheet 10 may not be known in advance, because individual pieces or shapes may be cut, punched or otherwise formed from sheet 10 to meet the requirements of a particular application. Due to the uniform distribution of openings 16 throughout sheet 10, any ultimately converted shape will likewise have uniformly distributed openings to allow air and moisture communication. Also, because of the uniform distribution of openings 16 there is no tendency for air or moisture to accumulate preferentially during application of the shape to the end use part. The openings 16 should be large enough to permit air, gas and moisture to pass therethough. Openings 16 preferably are circular in plan and have a diameter of less that about 0.030 inches in order to preserve structural integrity of sheet 10.

As best shown in FIG. 2, sheet 10 may also include a layer of adhesive 18 covering at least one of major surfaces 12, 14. Adhesive 18 may be water based acrylic adhesive, hot melt and/or solvent based adhesive. Preferably, a liner material 20 is releasably attached to the exteriorly disposed surface of adhesive layer 18. For example, liner material 20 may be a silicone coated release paper, polyethylene coated release paper, mylar, or some other material that is easily detached to expose adhesive 18 when attaching sheet 10 to a surface.

An apparatus A for forming perforated CCF is best shown in FIG. 3. Apparatus A includes a supply section 22 for holding sheet insulation 24, a cylindrical nip roller 26 spaced from supply section 22, and an aerator roller 28. A motor 30 is operably associated with nip roller 26 via belt 32 for causing axial rotation of nip roller 26. Supply section 22 may include a rod for holding a roll 24R of the sheet insulation 24.

As best shown in FIG. 4, aerator roller 28 includes a plurality of spaced projections 34. Preferably, projections 34 are uniformly spaced from each other. For example, projections 34 may be spaced from each other by at least about 0.125 inch. Projections 34 may be formed from polypropylene, steel, aluminum, or any material having sufficient rigidity sufficient to pierce sheet insulation 24. Projections 34 have a length sufficient to pierce through insulation 24. Projections 34 may be either tapered or cylindrical.

Aerator roller preferably has a length at least equal to the width of sheet insulation 24. Alternatively, two or more aerator rollers 28 may be axially aligned with each other so that rollers 28 have a combined total length at least equal to the width of sheet insulation 24. In this way, the entire surface of sheet insulation 24 may be perforated. Aerator roller 28 is parallel to nip roller 26 and spaced from nip roller 26 a sufficient distance so that the sheet insulation is perforated by projections 34 when passing therebetween to form perforated sheet 10, as best shown in FIG. 3.

Apparatus A may also include a guide roller 36 for guiding an adhesive coated release material 38 between first and second compression rollers 40, 42. Release material 38 preferably includes adhesive layer 18 and liner material 20. A roll 38R of release material 38 may be provided for supplying release material 38 to guide roller 36. Rollers 40, 42 are positioned so that release material 38 engages roller 42, and sheet 10 engages roller 40. Rollers 40, 42 are parallel to and aligned with nip roller 26 and guide roller 36, and rotate so that release material 38 and sheet 10 are compressed together therebetween. Rollers 40, 42 are sufficiently spaced so that release material 38 is compressed against and adhered to second major surface 14 of sheet 10. The adhesive of adhesive layer 18 may be pressure activated so that release material 38 is bonded to sheet 10 when they are passed between rollers 40, 42.

As shown in FIG. 3, guide roller 36 and compression rollers 40, 42 may be downstream of nip roller 26, so that release material 38 is adhered to perforated sheet 10. As such, release material 38 is not perforated after it is attached to sheet 10. An apparatus A′ according to another embodiment is configured so that release material 38 is bonded to sheet insulation 24 prior to perforation, as best shown in FIG. 5. Guide roller 36 and compression rollers 40, 42 are upstream of nip roller 26. Sheet insulation 24 and release material 38 are first bonded together between compression rollers 40, 42, and then simultaneously perforated by aerator roller 28.

Release material 38 is aligned with sheet insulation 24 prior to passing through rollers 40, 42 via guide roller 36. Release material 38 and insulation 24 are then compressed together by rollers 40, 42. The resulting multi-layer material, which includes insulation 24, adhesive layer 18 and liner material 20, is then passed between nip roller 26 and aerator roller 28, and pierced by projections 34 to form spaced openings 16, as best shown in FIG. 6. As noted above, nip roller 26 is preferably operably associated with motor 30 via belt 32, which causes nip roller 26 to rotate in a first direction D1. Aerator roller 28 rotates in a second direction D2 opposite the first direction as sheet insulation 24 passes therebetween, as shown by arrows D1, D2 in FIG. 6.

It should be understood that various apparatus configurations may be provided to form perforated CCF 10. An apparatus 80 for forming perforated CCF sheets 10 according to another embodiment is best shown in FIG. 8. Instead of using aerator roller 28 for forming openings 16 in sheet insulation 24, apparatus 80 includes a press 82 having a major surface 84 including a plurality of spaced projections 86 extending therefrom. Projections 86 are similar to projections 34, and may be uniformly spaced from each other. Projections 86 have sufficient rigidity to pierce sheet insulation 24, and have a length sufficient to pierce through insulation 24. Apparatus 80 may include supply section 22 spaced from press 82. Supply section 22 may include roll 24R of sheet insulation, as described above. An actuator 88 is operably associated with press 82 for causing major surface 84 to contact the sheet insulation 24 when passing under press 82. The sheet insulation is pressed against major surface 84, thereby perforating the sheet insulation by spaced projections 86 to form perforated CCF 10.

An apparatus 90 for forming perforated CCF sheets 10 according to another embodiment is best shown in FIG. 9. Instead of press 82, apparatus 90 includes a press having an upper die 92 and a lower die 94. Each of dies 92, 94 has a major surface 96, and major surface 96 of at least one of dies 92, 94 includes spaced projections 98 extending therefrom. Projections 98 are similar to projections 34 and 86, as described above. As shown in FIG. 9, lower die 94 includes projections 98. However, it should be understood that upper die 92 may include projections 98 instead, or both upper and lower dies 92, 94 may include projections 98. In addition, each projection 98 extending from one of dies 92, 94 may align with and be received in a corresponding recess in the other die when upper and lower dies 92, 94 are closed together. Apparatus 90 may also include supply section 22. Sheet insulation 24 is disposed between upper and lower dies 92, 94, and pressed therebetween so that major surfaces 96 of dies 92, 94 contact opposing sides of the sheet insulation so that projections 98 perforate the insulation thereby forming perforated CCF 10.

The perforated CCF sheet 10 is particularly useful for insulating metal panels or cabinets, particularly cabinets associated with HVAC applications. However, sheet 10 may be used in other applications requiring thermal and/or acoustic insulation, for example for insulating pipe, compressors, clothes dryers, dishwashers, etc. An insulated metal panel P according to the present invention is best shown in FIG. 7. Panel P includes a metal planar portion 50. Perforated sheet 10 is provided, having first major surface 12 exteriorly disposed and second major surface 14 adhered to portion 50 via adhesive layer 18. Openings 16 in sheet 10 permits any air to escape, which may otherwise be trapped between sheet 10 and surface 50. In this way, proper contact between sheet 10 and surface 50 is ensured, thereby achieving a proper fit and minimizing the possibility of de-lamination. In addition, surface 50 remains breathable to the environment adjacent first major surface 12, thereby reducing the possibility of microbial growth on panel P.

It will be apparent to one of ordinary skill in the art that various modifications and variations can be made in construction or configuration of the present invention without departing from the scope or spirit of the invention. Thus, it is intended that the present invention cover such modifications and variations, and as may be applied to the central features set forth above, provided they come within the scope of the following claims and their equivalents. 

1. Perforated closed cell foam insulation, comprising: a sheet of closed cell foam insulation having opposing first and second major surfaces; and a plurality of spaced openings extend from said first major surface through said second major surface.
 2. The insulation of claim 1, further comprising an adhesive layer covering at least one of said major surfaces.
 3. The insulation of claim 2, further comprising a liner material releasably attached to said adhesive layer.
 4. The insulation of claim 3, wherein said liner material is selected from the group consisting of silicone coated release paper, polyethylene coated release paper, and mylar.
 5. The insulation of claim 3, wherein said liner material and said adhesive layer include a plurality of openings aligned with said plurality of spaced openings.
 6. The insulation of claim 2, wherein said adhesive layer is water based acrylic adhesive.
 7. The insulation of claim 1, wherein said sheet has a thickness of at least about 0.030 inch.
 8. The insulation of claim 7, wherein said sheet has a thickness of between about 0.030 inch and about 2.0 inch.
 9. The insulation of claim 1, wherein said sheet is polyethylene closed cell foam insulation.
 10. An apparatus for perforating a sheet of closed cell foam insulation, comprising: a supply section for holding sheet insulation; a nip roller spaced from said supply section, said nip roller having a cylindrical configuration and a motor operably associated therewith for causing axial rotation of said nip roller; an aerator roller having a plurality of spaced projections, said aerator roller parallel to said nip roller and spaced from said nip roller a sufficient distance so that the sheet insulation is perforated by said spaced projections when passing therebetween.
 11. The apparatus of claim 10, wherein said supply section includes a rod for holding a roll of the sheet insulation.
 12. The apparatus of claim 10, further comprising a guide roller for aligning an adhesive coated release material with a side of the insulation.
 13. The apparatus of claim 12, wherein said guide roller is upstream said nip roller so that the sheet insulation and the release material are simultaneously perforated by said aerator roller.
 14. The apparatus of claim 13, further comprising first and second compression rollers intermediate and aligned with said nip roller and said guide roller, said rollers positioned so that the sheet insulation and release material are pressed together while passing therebetween.
 15. The apparatus of claim 12, wherein said guide roller is downstream said nip roller so that the release material is adhered to perforated insulation.
 16. The apparatus of claim 15, further comprising first and second compression rollers intermediate and aligned with said nip roller and said guide roller, said rollers positioned so that the perforated sheet insulation and release material are pressed together while passing therebetween.
 17. The apparatus of claim 10, wherein said spaced projections are uniformly spaced from each other by at least about 0.125 inch.
 18. The apparatus of claim 10, wherein said spaced projections are formed from a material selected from the group consisting of polypropylene, steel, and aluminum.
 19. The apparatus of claim 10, wherein said aerator roller has a length at least equal to the width of the sheet insulation.
 20. The apparatus of claim 10, wherein said apparatus includes at least two of said aerator rollers axially aligned with each other, said rollers having a total length at least equal to the width of the sheet insulation.
 21. A method of perforating closed cell foam insulation, comprising the steps of: providing a supply of closed cell foam sheet insulation; providing a pair of rollers parallel and adjacent to each other, one of the rollers having a plurality of spaced projections; and passing the sheet insulation between the rollers so that the spaced projections perforate the sheet insulation.
 22. The method of claim 21, including the further steps of: providing a supply of adhesive coated release material; aligning the release material with the sheet insulation; bonding the aligned release material to the sheet insulation; and perforating the bonded release material and sheet insulation simultaneously during said passing step.
 23. The method of claim 21, including the further steps of: providing a supply of adhesive coated release material; aligning the release material with the perforated sheet material; bonding the aligned release material to the perforated sheet insulation.
 24. An insulated metal panel, comprising: a metal planar portion; and a sheet of closed cell foam insulation having a first major surface adhered to said metal planar portion and an opposing second major surface, said sheet having a plurality of spaced openings extending from said first major surface through said second major surface.
 25. The metal panel of claim 24, wherein said panel comprises a portion of a metal cabinet.
 26. The metal panel of claim 24, wherein said metal cabinet is associated with an HVAC unit.
 27. The metal panel of claim 24, wherein said openings are uniformly distributed throughout said sheet.
 28. An apparatus for perforating a sheet of closed cell foam insulation, comprising: a supply section for holding sheet insulation; a press spaced from said supply section, said press having a major surface including a plurality of spaced projections; an actuator operably associated with said press for causing said major surface to contact the sheet insulation when passing under said press so that the sheet insulation is perforated by said spaced projections.
 29. The apparatus of claim 28, wherein said press includes an upper die and a lower die, at least one of said dies having said major surface including said spaced projections.
 30. A method of perforating closed cell foam insulation, comprising the steps of: providing a supply of closed cell foam sheet insulation; providing a press having a major surface including a plurality of spaced projections; disposing the sheet insulation under the press; pressing the sheet insulation against the major surface so that the sheet insulation is perforated by the spaced projections. 